kvm tools: Default guest cpu count to host cpu count

If user haven't specified cpu count for the guest, use
the amount of online cpus on the host.

Tested-by: Asias He <asias.hejun@gmail.com>
Signed-off-by: Sasha Levin <levinsasha928@gmail.com>
Signed-off-by: Pekka Enberg <penberg@kernel.org>

diff --git a/tools/kvm/kvm-run.c b/tools/kvm/kvm-run.c
index 8379a52b7688c1a30969e7d321027087e15fc65e..c01517f094f956bec9396b29b05e6dc2c0681e87 100644 (file)
--- a/tools/kvm/kvm-run.c
+++ b/tools/kvm/kvm-run.c
@@ -70,7 +70,7 @@ extern int  active_console;
 
 bool do_debug_print = false;
 
-static int nrcpus = 1;
+static int nrcpus;
 
 static const char * const run_usage[] = {
        "kvm run [<options>] [<kernel image>]",
@@ -410,6 +410,8 @@ int kvm_cmd_run(int argc, const char **argv, const char *prefix)
        signal(SIGQUIT, handle_sigquit);
        signal(SIGUSR1, handle_sigusr1);
 
+       nr_online_cpus = sysconf(_SC_NPROCESSORS_ONLN);
+
        while (argc != 0) {
                argc = parse_options(argc, argv, options, run_usage,
                                PARSE_OPT_STOP_AT_NON_OPTION);
@@ -440,7 +442,9 @@ int kvm_cmd_run(int argc, const char **argv, const char *prefix)
 
        vmlinux_filename = find_vmlinux();
 
-       if (nrcpus < 1 || nrcpus > KVM_NR_CPUS)
+       if (nrcpus == 0)
+               nrcpus = nr_online_cpus;
+       else if (nrcpus < 1 || nrcpus > KVM_NR_CPUS)
                die("Number of CPUs %d is out of [1;%d] range", nrcpus, KVM_NR_CPUS);
 
        if (!ram_size)
@@ -576,7 +580,6 @@ int kvm_cmd_run(int argc, const char **argv, const char *prefix)
 
        kvm__init_ram(kvm);
 
-       nr_online_cpus = sysconf(_SC_NPROCESSORS_ONLN);
        thread_pool__init(nr_online_cpus);
 
        for (i = 0; i < nrcpus; i++) {